"Bryan is a really positive guy and has been overwhelmed with the thoughts of every Evertonian," Everton's Twitter page quotes Oviedo as saying. "Today is an important day with surgery.
"We'll keep in mind the incredible level he showed this season and we can't wait to get him back. He's been very important for us.
"They say these things take 5-6 months, but I think Bryan may be less. We want to help him get back in time for World Cup."
Oviedo moved to Goodison Park last summer.